diff options
Diffstat (limited to 'src/libexpr/flake/lockfile.cc')
-rw-r--r-- | src/libexpr/flake/lockfile.cc | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/src/libexpr/flake/lockfile.cc b/src/libexpr/flake/lockfile.cc new file mode 100644 index 000000000..a40637824 --- /dev/null +++ b/src/libexpr/flake/lockfile.cc @@ -0,0 +1,284 @@ +#include "lockfile.hh" +#include "store-api.hh" + +#include <nlohmann/json.hpp> + +namespace nix::flake { + +FlakeRef flakeRefFromJson(const nlohmann::json & json) +{ + return FlakeRef::fromAttrs(jsonToAttrs(json)); +} + +FlakeRef getFlakeRef( + const nlohmann::json & json, + const char * version3Attr1, + const char * version3Attr2, + const char * version4Attr) +{ + auto i = json.find(version4Attr); + if (i != json.end()) + return flakeRefFromJson(*i); + + // FIXME: remove these. + i = json.find(version3Attr1); + if (i != json.end()) + return parseFlakeRef(*i); + + i = json.find(version3Attr2); + if (i != json.end()) + return parseFlakeRef(*i); + + throw Error("attribute '%s' missing in lock file", version4Attr); +} + +LockedNode::LockedNode(const nlohmann::json & json) + : lockedRef(getFlakeRef(json, "url", "uri", "locked")) + , originalRef(getFlakeRef(json, "originalUrl", "originalUri", "original")) + , info(TreeInfo::fromJson(json)) + , isFlake(json.find("flake") != json.end() ? (bool) json["flake"] : true) +{ + if (!lockedRef.input->isImmutable()) + throw Error("lockfile contains mutable flakeref '%s'", lockedRef); +} + +StorePath LockedNode::computeStorePath(Store & store) const +{ + return info.computeStorePath(store); +} + +std::shared_ptr<Node> Node::findInput(const InputPath & path) +{ + auto pos = shared_from_this(); + + for (auto & elem : path) { + auto i = pos->inputs.find(elem); + if (i == pos->inputs.end()) + return {}; + pos = i->second; + } + + return pos; +} + +LockFile::LockFile(const nlohmann::json & json, const Path & path) +{ + auto version = json.value("version", 0); + if (version < 3 || version > 5) + throw Error("lock file '%s' has unsupported version %d", path, version); + + if (version < 5) { + std::function<void(Node & node, const nlohmann::json & json)> getInputs; + + getInputs = [&](Node & node, const nlohmann::json & json) + { + for (auto & i : json["inputs"].items()) { + auto input = std::make_shared<LockedNode>(i.value()); + getInputs(*input, i.value()); + node.inputs.insert_or_assign(i.key(), input); + } + }; + + getInputs(*root, json); + } + + else { + std::unordered_map<std::string, std::shared_ptr<Node>> nodeMap; + + std::function<void(Node & node, const nlohmann::json & jsonNode)> getInputs; + + getInputs = [&](Node & node, const nlohmann::json & jsonNode) + { + if (jsonNode.find("inputs") == jsonNode.end()) return; + for (auto & i : jsonNode["inputs"].items()) { + std::string inputKey = i.value(); + auto k = nodeMap.find(inputKey); + if (k == nodeMap.end()) { + auto jsonNode2 = json["nodes"][inputKey]; + auto input = std::make_shared<LockedNode>(jsonNode2); + k = nodeMap.insert_or_assign(inputKey, input).first; + getInputs(*input, jsonNode2); + } + node.inputs.insert_or_assign(i.key(), k->second); + } + }; + + std::string rootKey = json["root"]; + nodeMap.insert_or_assign(rootKey, root); + getInputs(*root, json["nodes"][rootKey]); + } +} + +nlohmann::json LockFile::toJson() const +{ + nlohmann::json nodes; + std::unordered_map<std::shared_ptr<const Node>, std::string> nodeKeys; + std::unordered_set<std::string> keys; + + std::function<std::string(const std::string & key, std::shared_ptr<const Node> node)> dumpNode; + + dumpNode = [&](std::string key, std::shared_ptr<const Node> node) -> std::string + { + auto k = nodeKeys.find(node); + if (k != nodeKeys.end()) + return k->second; + + if (!keys.insert(key).second) { + for (int n = 2; ; ++n) { + auto k = fmt("%s_%d", key, n); + if (keys.insert(k).second) { + key = k; + break; + } + } + } + + nodeKeys.insert_or_assign(node, key); + + auto n = nlohmann::json::object(); + + if (!node->inputs.empty()) { + auto inputs = nlohmann::json::object(); + for (auto & i : node->inputs) + inputs[i.first] = dumpNode(i.first, i.second); + n["inputs"] = std::move(inputs); + } + + if (auto lockedNode = std::dynamic_pointer_cast<const LockedNode>(node)) { + n["original"] = fetchers::attrsToJson(lockedNode->originalRef.toAttrs()); + n["locked"] = fetchers::attrsToJson(lockedNode->lockedRef.toAttrs()); + n["info"] = lockedNode->info.toJson(); + if (!lockedNode->isFlake) n["flake"] = false; + } + + nodes[key] = std::move(n); + + return key; + }; + + nlohmann::json json; + json["version"] = 5; + json["root"] = dumpNode("root", root); + json["nodes"] = std::move(nodes); + + return json; +} + +std::string LockFile::to_string() const +{ + return toJson().dump(2); +} + +LockFile LockFile::read(const Path & path) +{ + if (!pathExists(path)) return LockFile(); + return LockFile(nlohmann::json::parse(readFile(path)), path); +} + +std::ostream & operator <<(std::ostream & stream, const LockFile & lockFile) +{ + stream << lockFile.toJson().dump(2); + return stream; +} + +void LockFile::write(const Path & path) const +{ + createDirs(dirOf(path)); + writeFile(path, fmt("%s\n", *this)); +} + +bool LockFile::isImmutable() const +{ + std::unordered_set<std::shared_ptr<const Node>> nodes; + + std::function<void(std::shared_ptr<const Node> node)> visit; + + visit = [&](std::shared_ptr<const Node> node) + { + if (!nodes.insert(node).second) return; + for (auto & i : node->inputs) visit(i.second); + }; + + visit(root); + + for (auto & i : nodes) { + if (i == root) continue; + auto lockedNode = std::dynamic_pointer_cast<const LockedNode>(i); + if (lockedNode && !lockedNode->lockedRef.input->isImmutable()) return false; + } + + return true; +} + +bool LockFile::operator ==(const LockFile & other) const +{ + // FIXME: slow + return toJson() == other.toJson(); +} + +InputPath parseInputPath(std::string_view s) +{ + InputPath path; + + for (auto & elem : tokenizeString<std::vector<std::string>>(s, "/")) { + if (!std::regex_match(elem, flakeIdRegex)) + throw Error("invalid flake input path element '%s'", elem); + path.push_back(elem); + } + + return path; +} + +static void flattenLockFile( + std::shared_ptr<const Node> node, + const InputPath & prefix, + std::unordered_set<std::shared_ptr<const Node>> & done, + std::map<InputPath, std::shared_ptr<const LockedNode>> & res) +{ + if (!done.insert(node).second) return; + + for (auto &[id, input] : node->inputs) { + auto inputPath(prefix); + inputPath.push_back(id); + if (auto lockedInput = std::dynamic_pointer_cast<const LockedNode>(input)) + res.emplace(inputPath, lockedInput); + flattenLockFile(input, inputPath, done, res); + } +} + +std::string diffLockFiles(const LockFile & oldLocks, const LockFile & newLocks) +{ + std::unordered_set<std::shared_ptr<const Node>> done; + std::map<InputPath, std::shared_ptr<const LockedNode>> oldFlat, newFlat; + flattenLockFile(oldLocks.root, {}, done, oldFlat); + done.clear(); + flattenLockFile(newLocks.root, {}, done, newFlat); + + auto i = oldFlat.begin(); + auto j = newFlat.begin(); + std::string res; + + while (i != oldFlat.end() || j != newFlat.end()) { + if (j != newFlat.end() && (i == oldFlat.end() || i->first > j->first)) { + res += fmt("* Added '%s': '%s'\n", concatStringsSep("/", j->first), j->second->lockedRef); + ++j; + } else if (i != oldFlat.end() && (j == newFlat.end() || i->first < j->first)) { + res += fmt("* Removed '%s'\n", concatStringsSep("/", i->first)); + ++i; + } else { + if (!(i->second->lockedRef == j->second->lockedRef)) { + assert(i->second->lockedRef.to_string() != j->second->lockedRef.to_string()); + res += fmt("* Updated '%s': '%s' -> '%s'\n", + concatStringsSep("/", i->first), + i->second->lockedRef, + j->second->lockedRef); + } + ++i; + ++j; + } + } + + return res; +} + +} |